Straight chain Alkanes (CnH2n 2)

1
Straight chain Alkanes (CnH2n2)
Methane CH4
                             
                  
          
Propane C3H8
2
Straight chain alkanes (contd)
n-Butane
                                                 

                               
Naming Alkanes Prefix-parent-suffix
(none) - but- ane
3
Branched Chain Alkanes
3-ethyl-2,3-dimethylpentane
                                          
3,3-dimethylpentane
2,2,3-trimethylbutane
4
Cyclic Alkanes
Cyclopropane (smallest)
Cyclobutane
,        
,       
,        
Cyclohexane
5
Substituted cycloalkanes
1,3-Dimethylcyclohexane
           
1,4-Dimethylcyclohexane
1-Butylcyclohexane
6
Isomerism in organic chemistry
Isomers are compounds with different physical and
chemical properties but same chemical
formula Two types Structural or Constitutional
isomers Stereoisomers or
Configurational isomers
Structural isomers All have formula C5H12
7
Stereoisomers
Stereoisomers are compounds that have same
molecular and structural formula, but differ in
spatial arrangement of the atoms There are two
main subtypes Diastereomers and
Enantiomers Geometrical isomers are also
stereoisomers but this type of isomerism arises
due to restricted rotation around rigid bonds in
the molecule. Example Cis 2-butene and
trans 2-butene
We will discuss more about
stereoisomers later on in lab !!